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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Seasonal Denning Behavior and Population Dynamics of the Late Pleistocene peccary Platygonus Compressus (Artiodactyla: Tayassuidae) From Bat Cave, Missouri

Woodruff, Aaron L., Schubert, Blaine W. 01 January 2019 (has links)
The late Pleistocene faunal assemblage from Bat Cave, central Ozarks, Missouri provides an opportunity to assess specific aspects of behavior, ecology, and ontogeny of the Rancholabrean species Platygonus compressus. All identifiable elements referable to this taxon were catalogued and examined, and a minimum number of individuals of 73 was determined for the sample. Evidence of seasonal behavioral patterns are reported for the first time in a fossil peccary. Maturation of individuals was assessed using the tooth eruption sequence and occlusal wear patterns for all tooth-bearing mandibular elements and isolated lower dentition. Approximate ages were established through comparison with the extant collared peccary. The presence of distinct, developmentally non-overlapping age groups suggests that P. compressus was seasonally present at the Bat Cave locality, with the cave functioning as seasonal shelter in which individuals would occasionally die. The study also suggests the peccaries engaged in synchronous, seasonal breeding behaviors. Demographic assessment of the Bat Cave peccary population suggests that younger individuals formed the bulk of the population at a given time with progressively older individuals becoming scarcer until the age of about 10 years, which matches the typical demographic patterns and life expectancy of extant peccaries.
2

Description, Taphonomy, and Paleoecology of the Late Pleistocene Peccaries (Artiodactyla: Tayassuidae) from Bat Cave, Pulaski County, Missouri

Woodruff, Aaron L 01 May 2016 (has links)
The late Pleistocene faunal assemblage from Bat Cave, central Ozarks, Missouri provides an opportunity to assess specific aspects of behavior, ecology, and ontogeny of the extinct peccary Platygonus compressus. All identifiable elements referable to this taxon were catalogued and examined, and a minimum number of individuals of 70 was determined for the sample. The presence of distinct, non-overlapping age groups suggests that P. compressus utilized Bat Cave on a seasonal basis. A predator-prey relationship with Canis dirus, the second most abundant vertebrate from the Bat Cave site, is also described in this study. Damage patterns suggest that the feeding patterns of C. dirus at Bat Cave were consistent with its extant relative, and that these predators would periodically enter the cave to hunt and/or scavenge peccaries. Overall, the fossil material from Bat Cave is virtually unweathered and represents one of the most extensive and well-preserved late Pleistocene faunas from the Ozarks.
3

Seletividade de herbicidas aplicados em pós-emergência em espécies de grama / Selectivity of post-emergence herbicides applied on turfgrasses species

Dias, Roque de Carvalho 23 February 2018 (has links)
Submitted by ROQUE DE CARVALHO DIAS (roquediasagro@gmail.com) on 2018-04-20T00:59:46Z No. of bitstreams: 1 Dissertação Roque 1.pdf: 5566286 bytes, checksum: 6c72537f585638e2c9c641329d843ab1 (MD5) / Approved for entry into archive by Maria Lucia Martins Frederico null (mlucia@fca.unesp.br) on 2018-04-20T12:21:20Z (GMT) No. of bitstreams: 1 dias_rc_me_botfca.pdf: 5488383 bytes, checksum: 9135485526aa6ccb4ff2034a5d777818 (MD5) / Made available in DSpace on 2018-04-20T12:21:20Z (GMT). No. of bitstreams: 1 dias_rc_me_botfca.pdf: 5488383 bytes, checksum: 9135485526aa6ccb4ff2034a5d777818 (MD5) Previous issue date: 2018-02-23 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / As plantas daninhas interferem nos gramados, prejudicando a sua formação, estabelecimento, qualidade e estética. Destaca-se dentre as diversas técnicas o uso de herbicidas, entretanto, são escassas as informações referentes a seletividade desses produtos em gramados. Desse modo, o objetivo desse trabalho foi avaliar a seletividade de herbicidas aplicados em pós-emergência sobre as espécies Axonopus compressus (grama São Carlos), Paspalum notatum (grama Batatais), Zoysia japonica (grama Esmeralda) Cynodon dactylon x Cynodon transvaalensis (grama Bermuda - Tifton 419). Foram realizados dois experimentos, todos em casa de vegetação e repetidos em diferentes momentos. As quatro espécies de grama foram transplantadas em vasos com capacidade de 2 L e aos 40 dias após o transplantio foram realizadas as aplicações dos tratamentos. Os tratamentos constituíram-se pela aplicação de 13 herbicidas (g i.a. ha-1): chlorimuron-ethyl (15); halosulfuron (112,5); imazapyr (125,0); metsulfuron-methyl (2,4); dicamba (288); triclopyr (600); 2,4-D (2010); clomazone nas formulações convencional e microencapsulada (1200); atrazine (1250); bentazon (600); flumioxazin (30); sulfentrazone (600), além de tratamento controle (sem aplicação de herbicida) para cada espécie estudada. O delineamento experimental utilizado foi inteiramente casualizado com quatro repetições. As avaliações da taxa de cobertura verde (TCV) das espécies de gramas foram realizadas aos 0, 3, 6, 9, 12, 15, 18, 21, 24, 27, 41, 48, 55 e 62 dias após a aplicação (DAA); altura e fitointoxicação nos mesmos período da TCV exceto ao 0 DAA. Avaliou-se também aos teores de clorofila total e carotenoides aos 9, 18 e 27 DAA e biomassa seca das aparas aos 27 e 62 DAA. Os dados obtidos foram submetidos à análise de variância pelo teste F, sendo para os teores de clorofila total e biomassa seca das aparas, às médias comparadas pelo teste Tukey (p≤0,05). Já os resultados de TCV, fitointoxicação e altura dos herbicidas os dados da diferença mínima significativa (DMS) foram representadas nos gráficos. Os efeitos dos herbicidas observados nas diferentes espécies de grama foi dependente da espécie, herbicida, época e recuperação do gramado. Os herbicidas que apresentaram potencial de seletividade para o gramado de A. compressus e P. notatum foram a atrazine, bentazon, chlorimuron-ethyl, dicamba, flumioxazin, halosulfuron, metsulfuron-methyl e sulfentrazone. Já para o gramado de Z. japonica foram considerados atrazine, bentazon, chlorimuron-ethyl, dicamba, halosulfuron, metsulfuron-methyl e 2,4-D flumioxazin e sulfentrazone. Com exceção do triclopyr, os produtos seletivos para Z. japonica podem também ser considerados seletivos para a grama Tifton 419. / Weeds interfere with turfgrass, hampering their formation, establishment, quality and aesthetics. Among the several techniques, the use of herbicides stands out, however, the information regarding the selectivity of these products in turfgrass is scarce. Thus, the aim of this work was to evaluate the selectivity of herbicides applied in post-emergence on the species Axonopus compressus (broadleaf carpetgrass), Paspalum notatum (bahiagrass), Zoysia japonica (japanese lawn grass), Cynodon dactylon x Cynodon transvaalensis (bermudagrass -Tifton 419). Two studies were conducted, all in a greenhouse and repeated at different times. The four turfgrass species were transplanted in vessels with a capacity of 2 L and at 40 days after transplanting the applications of the treatments. The treatments consisted of the application of 13 herbicides (g i.a. ha-1): chlorimuron-ethyl (15); halosulfuron (112.5); imazapyr (125.0); metsulfuron-methyl (2.4); dicamba (288); triclopyr (600); 2,4-D (2010); clomazone in conventional and microencapsulated formulations (1200); atrazine (1250); bentazon (600); flumioxazin (30); sulfentrazone (600), in addition to control treatment (without herbicide application) for each species studied. The experimental design was completely randomized with four replicates. The green cover rate (TCV) evaluations of the turfgrass species were performed at 0, 3, 6, 9, 12, 15, 18, 21, 24, 27, 41, 48, 55 and 62 days after application (DAA); and height and phytointoxication, in the same TCV period, except for 0 DAA. The levels of total chlorophyll and carotenoids were evaluated at 9, 18 and 27 DAA and dry biomass of the shavings at 27 and 62 DAA. The obtained data were submitted to analysis of variance by the F test, being the total chlorophyll content and dry biomass of the chips, compared to the Tukey test (p≤0.05). On the other hand, the results of TCV, phytotoxification and herbicide height showed the minimum significant difference data (DMS). It was observed that the selectivity of the herbicides was dependent on turfgrass species, herbicide, season and plants recovery. The herbicides with selectivity potential for P. notatum e A. compressus were atrazine, bentazon, chlorimuron-ethyl, dicamba, flumioxazin, halosulfuron, metsulfuron-methyl e sulfentrazone. For the Z. japonica were, atrazine, bentazon, chlorimuron-ethyl, dicamba, flumioxazin, halosulfuron, metsulfuron-methyl, sulfentrazone and 2,4-D. With the exception of triclopyr, selective products for Z. japonica can also be considered selective for Tifton 419 tufgrass.
4

Pleistocene Peccaries from Guy Wilson Cave, Sullivan County, Tennessee.

Nye, April Season 14 August 2007 (has links) (PDF)
Descriptive and taphonomic analyses of undescribed Pleistocene Tayassuidae from Guy Wilson Cave within the East Tennessee State University and McClung Museum collections revealed a MNI of 16 Platygonus compressus and 2 Mylohyus from left femora and isolated teeth, respectively. Linkage between upper dentition and species identification is suggested by comparing Mylohyus fossilis to M. nasutus from other Pleistocene-aged sites. Long-bone NISP and age profiles show a predominance of Platygonus adults. Tayassuidae upper canines, likely Platygonus, suggest sexual dimorphism. Long bones were analyzed for carnivore damage and utilization revealing light utilization similar to that caused by modern wolves. Long bone weathering is predominantly light and suggests limited exposure prior to burial. Results indicate the cave was likely used as a carnivore den, possibly from dire wolf, for a period of time. No stratigraphical excavation data were available for either collection; therefore, additional excavations are needed to confirm these findings.

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